RUDN Journal of Agronomy and Animal Industries

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The efficiency of using the feed additive Bacell-MT (the microbial mass of live bacteria Bacillus subtilis 945 (B-5225) in an amount of not less than 1×108 CFU/g, the microbial mass of live bacteria Bacillus amylolique faciens KLS (B-14047) in an amount of not less than 1×108 CFU/g) in the diet of dry cows during their preparation for calving, as well as to increase productivity and improve the condition of the offspring. The studies were conducted on Holstein cows of red-and-white color. The cows were selected on the principle of pairs of analogues and divided into three groups of 20 heads each. The conditions of keeping, feeding and water supply of animals of the experimental and control groups were the same, the only difference was that the experimental groups received the feed additive Bacell-MT, the control group received a basic diet. It was found that the use of Bacell-MT contributes to the safety of livestock, normalization of biochemical parameters of blood, improvement of the quality of milk and offspring. A recommendation is given for the use of probiotic supplements in dry period diets to prevent metabolic disorders and ensure the health of both cows and their offspring.

The dynamics of live weight growth, morphometric indices of carcasses, and chemical composition of muscles were studied on Ross 308 cross chickens up to 42 days of age raised on diets with increased fi content and inclusion of multi-enzyme complex of protease and xylanase. Experimental studies were carried out in the feeding department of FSC ARRTPI, and vivarium of GSC “Zagorskoe EBFˮ, and morphometric and chemical parameters were determined at the Department of Veterinary Medicine of the Peoples’ Friendship University of Russia. When broilers reached the age of 28, 35, and 42 days, 3 chickens from each age group were slaughtered. Day-old chicks served as starting material. At the end of the growing period, the live weight of birds was determined, slaughtered, and morphometric indices of carcasses were studied; superficial pectoral muscles were subjected to histological studies, and shin muscles were subjected to chemical studies. Live weight of chickens from the control group reached 2432 ± 38.3 g by 42 days of age, experimental chickens - 2556 ± 28.5 g, at p ≤ 0.05 with a difference of 124 g, or more by 4.85%, carcass weight - 1778 and 1870 g respectively, with a difference of 4.20% ( p ≤ 0.05). On the 42nd day, the thoracic part of the carcass is 35.19…36.39%, increasing with age - by 1.20%, and the relative mass of the femoral part decreased by 0.68%, the tibia - by 0.72%. Pectoral muscles increased in: protein content - by 22.10%, fat - by 1.89%, and moisture - by 6.15%. The experimental group of chickens showed an increase in the diameter of muscle fi of superfi pectoral muscles by 42 days in 6.8 times. The structure of the muscle tissue of the superfi pectoral muscles was found to be disturbed at various stages.

The aim is to study changes in the concentration of C-reactive protein, which serves as an indicator of inflammatory processes in diagnostics, in the exudate from the uterine cavity of dairy animals after parturition. In the period from 2020 to 2024, in the Volgograd Region, scientific work was carried out on the basis of LLC ʺSP ʹDonskoyeʹʺ. The level of C-reactive protein in the fluids obtained after uterine lavage and in plasma samples was determined using enzyme-linked immunosorbent assay (ELISA) on a series of samples and a diagnostic kit for this biomarker. The studies in the laboratory were carried out according to the instructions provided by the manufacturer of the analytical equipment and the necessary reagents. The study revealed modifications in the content of C-reactive protein (CRP) both in blood plasma and in the uterine syringing solutions in cows throughout the experiment. In the uterine lavage solutions of healthy cows from the control series, the average CRP level reached 23.62 ± 8.94 ng/ml, whereas in the animals of the experimental group suffering from metritis this indicator was significantly higher and amounted to 67.26 ± 26.32 ng/ml. There is a spread in the concentrations of C-reactive protein in cows of the two groups, which indicates their different immune activity. The study aims to evaluate C-reactive protein as a potential indicator of inflammation during uterine healing after labor. Based on the results, it can be concluded that determining the concentration of this protein in uterine fluid may be an effective method for identifying inflammatory conditions in this organ.

Soybean cultivars are characterized mainly by morphological and biochemical traits. However, researchers encounter difficulties when trying to use these parameters in cultivar identification and differentiation, making it difficult to work with closely related cultivar lines. Microsatellite markers or SSRs (simple sequence repeats) are an excellent tool for variety identification and differentiation, revealing the degree of genetic relatedness and copyright protection. The aim of the research was to obtain molecular genetic formulas for cultivated and wild soybean varieties with subsequent identification of their genetic relatedness. The object of the study was 51 samples of soybean (39 cultivars and 12 wild forms). Genomic DNA was isolated from the studied samples and then amplified. The obtained amplicons were separated in 2% agarose gel and the length of the fragments was detected in two replications. Nine microsatellite loci (Satt1, Satt2, Satt5, Satt9, Soyhsp176, Satt681, Sat_263, Satt141, Satt181) were used for molecular genetic characterization. Results demonstrating the length of each locus were analyzed by the UPGMA algorithm to record genetic relatedness or remoteness. The molecular genetic formulae of the studied samples were obtained, which can be further used to compile genetic passports. Based on the UPGMA algorithm, 51 soybean genotypes were grouped into 13 main clusters. Most of the soybean wild forms growing in the Amur Region demonstrated genetic proximity due to belonging to three closely located clusters. However, the soybean wild form from the Khabarovsk Territory (Dikaya soya 31) and one of the forms from the Amur Region (KZ-6337) were genetically distant from other groups of soybean wild forms. These results indicate the adequacy of the use of 9 SSR locuses for identification tasks, identification of relatedness and further passportization of soybeans.

The purpose of the recent study was to evaluate the effectiveness of chitosan nanoparticles (CSNP) and black poplar buds extract (BpE) to protect potato tubers from post-harvest Fusarium dry rot. A high virulent Fusarium isolate was recovered from natural infected tubers in Astrakhan region and subjected to molecular identification using ITS rDNA gene and identified as Fusarium sumbucinum . CSNP were successfully prepared by ionic gelation method with size ranged from 79.4 to 186.4 nm as observed by scanning electron microscopy (SEM), and a positive zeta potential of 53.1 mv. CSNP at a concentration of 2 g/l, and BpE at a concentration of 40 g/l completely inhibited Fusarium fungal growth on PDA medium in vitro . CSNP at a rate of 20 g/t and BpE at a rate of 400 g/t significantly reduced the incidence of dry rot under natural infection during 8 months of storage by 54.7 and 58.5% and reduced the disease index by 65.7 and 72.3%, respectively, and there was not a significant difference between the two treatments. These results demonstrate the potential of CSNP and BpE for protection of potato tubers against the fungal postharvest decay.

The experience and researches of Buzdyak forestry were analyzed. The stages of development of forestry in Buzdyak district of the Republic of Bashkortostan were considered. The forestry carries out the study, accounting, reproduction and protection of forests, the regulation of forest use, etc. The forest fund of the Buzdyak administrative district is territorially related to Tuymazinsky forestry and is divided into 3 district forestries: Buzdyakskoye (5526 ha), Kuzeyevskoye (6958 ha) and Yarmunchinskoye (8195 ha). It was found that coniferous trees dominate in the created protective forest stands, such as Scots pine and Russian larch, characterized by a longer period of functioning of protective properties. According to forest vegetation zoning, the forests of all three district forestries are classified as protective and exploitation forests. Based on long-term scientific and production experiments conducted on the territory of the republic and the district, recommendations were given to increase productivity and protective properties of forest plantations. In the projects being developed, when planting protective forest belts, the percentage of such species as pine and larch, which have a longer lifespan and provide a greater yield of commercial timber during thinning, is increased. The task is to create not individual forest plantations or even individual belt systems, but agroforestry complexes that are balanced with the environment.

The study aims to present quantitative features of fetal blood flow in dogs based on ultrasonography and ultrasonometry data to predict intrauterine fetal development. Based on the use of ultrasonography and ultrasonometry, the umbilical cord vessel resistance index in dogs was established. The advantages of the umbilical artery resistance index in comparison with other indices in assessing fetal maturity and fetal distress were revealed. The features of blood flow were established in normally developing fetuses and in fetuses with intrauterine pathologies. The developed methodology of a complex quantitative assessment of fetal blood flow in dogs is an effective tool for predicting the course of pregnancy, diagnosing intrauterine development pathologies, and making informed decisions regarding pregnancy management and parturition in dogs.

In modern physiology, the features of the functional state of the body are increasingly being studied not in terms of breeds, age, and animal husbandry technologies, but in terms of DNA markers. Therefore, in this aspect, it is interesting to compare the functional state of the antioxidant system of the Equus caballus organism depending on the breed and DNA markers. The purpose of this study was to conduct a comparative analysis of the functional state of the antioxidant system of Equus caballus horses of different breeds and with different genotypes according to the GRM8 gene. The study of the physiological characteristics of the antioxidant system of the body of Equus caballus of Russian breeding was carried out from 2005 to 2023. The study involved 70 breeding stallions belonging to 9 breeds. The best superoxide dismutase activity was detected in the blood of stallions with the CC/AA genotype according to SNPrs395286150/394524550: 11.4 and 2.3% more ( p < 0.05) than in carriers of the CT/AG and TT/GG genotypes, respectively. Catalase (CAT) activity was at a comparable level but with significant differences. We observed the highest CAT activity in the blood of stallions with the CC/AA genotype according to SNPrs395286150/394524550, which is 1.8% more in carriers of the CT/AG genotype and 7.9% ( p < 0.05) more in carriers of the TT/GG genotype. Against this background, the activity of glutathione peroxidase (GPx) was the highest in the blood of stallions carrying the CT/AG genotype according to SNPrs395286150/394524550, which is 9.8% more ( p < 0.05) in stallions of the CC/AA genotype and 14.8% more ( p < 0.01) in stallions of the TT/GG genotype. The amount of malondialdehyde (MDA) was highest in carriers of the GG genotype according to SNPrs1147388106, which is 13.4% more ( p < 0.01) in carriers of the GA genotype and 2.6% more in carriers of the AA genotype according to SNPrs1147388106. The study of the functional state of the antioxidant system of the horse body, depending on the breed, also shows the presence of significant differences between breeds of different uses.

Decrease in compensatory mechanisms of natural resistance due to changes in composition of evolutionarily formed microbiocenoses, increases risks of developing a syndrome of excessive growth of antibiotic-resistant microorganisms. The aim of the study was to analyze the dynamics of changes in bacteriological and morphofunctional parameters with a decrease in colonization resistance of the intestine of birds. To assess quantitative and species composition of microorganisms, the colonization index of bacteria isolated from the caecum contents of intestine of clinically healthy and sick birds was considered. The dynamics of changes in morphofunctional parameters during the dissemination of pathogenic bacteria into tissues and organs was studied using cytological and histochemical data. The number of microorganisms isolated from the caecum contents of intestine of sick birds significantly increased, the colonization index of lactose-positive bacteria was 0.247…0.283; lactose-negative bacteria - 0.657…0.730. With excessive bacterial contamination of ileocecal part of intestine and translocation of pathogens outside gastrointestinal tract, signs of dystrophy, necrosis and rejection of epithelial cells of mucous membrane of respiratory and digestive systems developed. The initiation, development and outcome of the infectious process are mediated by stability of homeostasis of susceptible macroorganisms and realization of pathogenic potential of isolates producing adhesive antigens, bacteriocins, hemolysins, and cytotoxins.